In Finland, a dental subsidization reform, implemented in 2001-2002, abolished age restrictions on subsidized dental care. We investigated income-related inequality in oral health-related quality of life (OHRQoL) and its determinants among adult Finns before and after the reform. Three cross-sectional postal surveys, focusing on perceived oral health and the use of dental services among people born before 1971, were conducted in 2001 (n=2,046), 2004 (n=1,728), and 2007 (n=1,560). Five measures, based on the Oral Health Impact Profile-14, were used as indicators of OHRQoL. Income-related inequality and associated factors were analysed using the concentration index and its decomposition. Prevalence, extent, and severity of oral health impacts were slightly lower in 2007 than in 2001. The oral health impacts were concentrated, at all study time points, among individuals with lower income. Most of the inequality was related to self-perceived general health, tooth loss, and income. Contributions of time since the last dental visit and satisfaction with the last treatment period to the inequality decreased from 2001 to 2007. However, the contributions of these factors were already small (10-20%) in 2001. In general, OHRQoL improved slightly; however, no clear or dramatic change in inequality in OHRQoL was seen after the reform.